Bubbly Basin was announced as the first expansion area for Pokémon Pokopia’s Expansion Pass.
The paid Expansion Pass adds post-launch content beyond the base game. Bubbly Basin was presented as its first major area, expanding the world with additional activities, scenery, outfits, and Pokémon-related content rather than merely adding a small cosmetic item.
The Expansion Pass is distinct from the game’s launch package and from free updates. Nintendo’s product information describes separate parts released on a schedule, with later parts planned to add further features. This staged structure means Bubbly Basin identifies the first expansion section, not the name of the entire pass.
Players can also encounter similarly themed location names in Pokémon media and fan discussions, which makes exact wording important. The official expansion name uses the alliterative title “Bubbly Basin,” and both words begin with the letter B.